When it comes to science fiction films, everyone has a definition of campiness — a designation that all too often skews to the truly silly or the hilariously exaggerated.

The problem with “campy” films, like the ridiculous spider-invasion thriller “Eight Legged Freaks” or the low budget, strings-and-wires schlock known as “The Lost Skeleteon of Cadavra,” is that they are limited by an agenda. By exerting so much effort in looking unprofessional and unsophisticated, they draw out our skepticism instead of our affection.

“Automatons,” the unexpectedly mesmerizing, low-budget spectacle (it bills itself as “a low-tech effects film about the horrors of war and robots”) set to light up the Pioneer Theater for an impressive 16-night run, is sure to be dismissed by some as just another campy robot fantasy. A story about a futuristic world, shoddily filmed on grainy black-and-white stock, composed almost entirely on one set, and featuring audio imperfectly dubbed over the action, the only thing more peculiar than the aesthetic is the physical movement of the movie’s stars — the robots. Seemingly constructed out of cardboard, the robots shuffle along at a snail’s pace, lumbering about as if trapped underwater.

Here’s a movie with ideas as big as any to be found in “War of the Worlds,” but with a budget that must have been a fraction of what Steven Spielberg spent on catering.

This is campiness not out of choice, but out of necessity — the kind of camp that leads one to secretly relish the likes of “The Day the Earth Stood Still,” “The Outer Limits,”or even the original “Doctor Who.” It’s not a film of compromise but of sheer determination, refusing to be defined by its budget and liberated by a decision to overcome its bank account with sheer imagination.

It says something about the movie that it takes quite a while to learn where — or how — the story takes place. Structured smartly as a mystery, beginning in the fog of a brave new world, writer and director (and producer) James Felix McKenney grounds us in a bunker, watching a woman who seems to do little else besides fix broken robots. Day after day, the Girl (Christine Spencer) polishes them up, sends them out through a series of metallic doors, and then watches their signals on her radar as they attack other robots out in the barren, lifeless outdoors.

Mission after mission, she dispatches these drone fighters, some of which return damaged, some of which fail to return at all. She cleans and she preps, and occasionally the television monitors near her turn on, revealing the faces of a woman or a man — the only other faces we see in this vision of the future. The former, we come to learn, is that of an enemy commander, apparently another woman (Brenda Cooney) in much the same position as our heroine — with her own robot army and the ability to send out radio signals that turn the Girl’s robots against her.

The man (Angus Scrimm, well known to horror fans), however, is the only voice in the film that comes to matter. Seen in flashback, through a recording he left for the Girl to find, this man is the haunting voice of the past, informing the present of how this misery came to be. Listening to him, we learn of how a great war was launched — a relentless war against those who would seek to destroy the prosperity of the Girl’s country — and how these robots were created to help forge freedom around the globe. As the Girl continues to unearth videos left by the Man, they become more cryptic and foreboding. The war is not going well, he says in later recordings, and as the landscape around him becomes increasingly ravaged by violence, he comes to question the worth of all he has believed and fought for.

This is the extent of the movie’s tools: a character in the present, toiling over her war preparations, a character in the past, putting the war in context, and the bizarre one two-punch of shuffling robots and radar beeps to convey battles now under way. Yet somehow, against all the expectations that have been built up by big-budget blockbusters, the film works, as Mr. McKenney patiently unravels the reality of his future nightmare.

From the opening shot we’re drawn in, unsure why these robots are fighting, why they are moving so slowly, or who’s really controlling them. Even the film’s grainy black-and-white photography, often interrupted by a pulsating white strobe light, gives the movie an exciting, disorienting glow. The soundtrack, divided among the sounds of ray guns, radar bleeps, recorded voices, and resounding silence, offers a wild variation in texture.

And it all ends with a punch, as Mr. McKenney’s claustrophobic technique becomes his way not only of accommodating his small budget, but of evoking the film’s themes of isolation and denial. Sure, it’s campy. We’ve got all those robots and that post-apocalyptic jargon, all that bleakness and those weak special effects. But as is true with all the great experiments in camp, the frills don’t matter when there are firm — and fascinating — ideas behind them.

If Hollywood’s star-driven, risk-avoiding formulas have proved anything, it’s that beauty can only beguile for so long. And if great campy sci-fi has offered any meaningful counterpoint, it’s that the ugliest of visions can also be the most captivating.

Through December 26 (155 E. 3rd St., between Avenue A and Avenue B, 212–591-0434).